Choosing the correct battery for your application is paramount.
Batteries are not all the same and not all suited for every application.
If you are not connected to the utility grid, you need somewhere to store your energy.
If you are connected to the utility grid, the batteries will save enough energy to cushion you when shortages in the grid occur.
Since the panels produce energy during the day, and you may not use all the energy at the time, a stable power bank is essential to store this energy.
What is Battery Storage?
We talk about solar batteries as a device which store the energy generated from the solar panels for later use. The solar batteries ensure that you can continue to enjoy solar power even after the sun has disappeared for the evening, during a power outage or the even during energy demand peaks (Peak Shaving). These batteries can be used in residential properties, as well as in commercial buildings, they can be used in conjunction with a grid connection or others are more suited to a "off grid" situation.
When building a solar power system, solar batteries should be a priority as they will determine how effective the system will be to you.
Using the batteries, you optimize your ability to use solar power daily. In instances where you require more energy than your panels produce, you can readily use the stored energy from the batteries.
Domestic Battery Storage systems can be quite different to what you may expect as the Alpha Smile 3 & 5 found here
The solar batteries work by storing the energy generated from the solar panels during the day. They save the energy in the form of DC energy and therefore, you will require an inverter to convert the DC energy into AC energy.
Another vital component of solar batteries is the solar charge controller. This helps to ensure that the energy produced during the day does not overcharge the batteries.
Also, it prevents the power stored in the cells from running back to the panels and draining the batteries over the night.
To better understand how you can easily choose the right solar battery, you should first know the broad classes of these batteries.
There are three options of cells you can choose from which include the sealed lead-acid, flooded lead-acid, and lithium batteries.
For the longest time, the most popular solar batteries for a home have been the flooded lead-acid batteries. This model of solar cells has been in use for over 150 years and has been a great asset, especially to the off-grid systems.
Flooded lead-acid batteries, also referred to as wet cells, are very affordable and are also 99% recyclable.
With their design, they can easily handle the daily charge cycling. The significant advantages of these batteries include their low purchase cost, reliability, and safety. However, this category of cells has a good measure of drawbacks.
These batteries are known to produce a byproduct in the form of a gas, and therefore, ventilation is essential where they are located. Another major disadvantage is that they are bulky and corrosive. Also, they demand maintenance checks regularly. The batteries must also be kept in an upright manner to avoid leakage.
Flooded lead acid batteries are made of cells whose plates must be kept underwater for them to function correctly. This is the reason they are referred to as “flooded.” You need to check and add water every after 1-3 months to ensure the plates remain submerged.
For those who don’t mind the regular maintenance and monitoring, these can be the right choice. They are also the most affordable category of solar batteries.
However, due to the multiple drawbacks, many most homeowners are shifting to the use of other models which have fewer maintenance demands.
The second category of batteries is the AGM Batteries. From the early 1980s, this technology started gaining popularity with a sealed lead-acid battery being made for the military vehicles, aircraft, and UPS. These AGM batteries are part of a category of lead-acid batteries called the sealed lead acid.
In this form of a lead-acid battery, a fiberglass matt is used to absorb the electrolyte.
In the AGM batteries, the plates are either flat just like in the flooded lead-acid, or coiled into a spiral resembling those in Optima batteries.
One primary advantage of AGM batteries is that they possess a lower internal resistance than that in flooded cells. Therefore, these batteries can endure higher temperatures, as well as discharge slowly, more than the rest of the batteries.
Unlike the flooded lead cells, the cells in AGM batteries are leak-proof, and they also require less or no ventilation. However, just like the flooded batteries, they use the same charging voltage and tend to be more well-suited for solar electricity systems.
The other advantages of using AGM batteries include the fact that they are not hazardous, their resistant to cold temperatures, and they are relatively lightweight.
Also, they are less prone to heating up (due to the low internal resistance), and they can also preserve a static charge for long periods. AGM batteries, unlike the flooded batteries, have a longer lifespan and just slightly expensive than their counterparts.
Generally, they are an excellent choice for an off-grid solar system.
Another type of sealed lead-acid batteries is the GEL Battery. These batteries specialize in deep-cycle applications and use fumed silica to form the thickening agent for the electrolyte. The fumed silica helps to make the cells sturdier.
Some other advantages of Gel batteries include that they durable, requires no maintenance, and they have high resistance to vibrations and shock. The cells also work well in both hot and cold temperatures and have great life-cycles. Also, with the viscous electrolyte, the cells become less prone to leakage in case of damage.
Nonetheless, GEL batteries have more disadvantages than the other types of batteries, making them less popular. These batteries are vent less and they self-discharge a bit faster than the flooded cells.
Other common disadvantages of this category of batteries include their narrow charging profiles, and they are easily damaged if charging is not done right.
The batteries also lack ample amp-hour capacity, and their low charging voltage can make them disposed to accidental overcharge.
Especially with solar power systems, electricity generation is a bit variable and can cause this overcharging. In addition to the numerous drawbacks, Gel batteries are also more expensive than the flooded lead-acid batteries.
The last category in this list is lithium batteries. They consist of a newer technology that became available from the 1990s and has been in use mostly in cellphones and laptops. However, the cells have become increasingly popular in the renewable energy industry in recent times.
Although more expensive than other types of batteries, lithium batteries offer multiple benefits that compensate for the price.
These advantages include longer lifespan, higher efficient power usage, no maintenance, deeper discharges (more storage capacity), no gas emission, and more. These can typically be the best batteries for solar panels.
In the recent past, people have increasingly shifted from the traditional flooded lead-acid batteries and are more focusing on lithium-based cells.
They are also instrumental in cordless power, including cordless air compressors, and cordless impact wrenches among others. These batteries are small in size and are significantly light judging by their high capacity.
Lithium-ion batteries are easy and efficient to charge, and also, they have long lifespans. The long lifespan is the main advantage of lithium batteries as it ranges from 3000-5000 cycles.
Their high and efficient charge and discharge also is a plus as it helps to optimize the power generation from the solar panels.
The low discharge feature is ideal in solar installations as it helps retain power for more extended periods for later use. With all these benefits lithium batteries are an excellent choice to make up your battery bank.
Any solar system, whether small or large, grid-tied or off-grid, lithium batteries are ideal for all. One major disadvantage of lithium solar batteries is their cost.
They can cost as much as four times more than the flooded solar cells, the second disadvantage is that lithium could prove problematic when you try to get rid of them. Usually you can return them to your supplier who will have a process of returning these batteries to the manufacturer.
The voltage question may seem irrelevant, but it is essential. Before you buy and install your battery, you should decide which voltage your battery system will be made of.
For example, the batteries can either be 12V, 24V, or 48V. Which fits your needs better? This is something you should be aware of before the installation.
Since it is challenging to change the voltage after installing your power storage system, it becomes critical, therefore, to make the correct choice. The 12V battery is the purest form of battery and the most commonly used one in cars, boats, RVs, and more. If you require a simple power storage system, then the 12V battery system will be enough for you.
Presently the 24V and the 48V storage systems are the most commonly used in the solar systems. The reason behind this is the technical advantages they have as compared to the 12V.
In essence, higher DC Voltage translate to lower costs. It also translates to a lower current for a similar amount of power.
For example, 2,000 Watt is equal to 166 amp @ 12V, 2,000 Watt is equal to 83 amp @ 24V and 2,000 Watt is equal to 41.5 amp @ 48V
Moreover, as more and more customers seem to require more energy over the years, the 12V DC system is not ideal. If for instance, your solar panels exceed 500 watts, you should consider a 24V system. On the other hand, if you plan to live off-grid, the 48V system will be ideal.
Even with all that information, you are still not ready to jump into that purchase.
There are several factors you should always research before making that final choice. These features include:
The battery size is the first most crucial thing you ought to consider when buying a solar battery. The size in this context means the energy storage capacity of the battery. Although the physical size of the battery will also matter based on the space you have for installation, the capacity is most important.
When looking at size, you should consider both the capacity and the power rating. For instance, a battery with low power rating and high capacity will only power a few appliances in your home, but for a long time.
On the other hand, if it has a low capacity but high rating power, it will power most of your appliances but for a shorter period.
Therefore, you should look for a battery with high capacity, as well as a high power rating. With this kind of a cell, you can power multiple appliances at your home, and for more extended periods.
An easy to use to determine what battery size to take is this Battery Calculator
If you don't have much prior knowledge on the solar systems, you require a battery system that is easy to install. Essentially, it is wise to seek advice from people who have prior experience or better still, professionals who deal with these kind of things on a daily basis.
If you want a battery system that is maintenance-free, easy to install, and that requires relatively low space, the lithium-ion batteries are your best choice.
Don’t go for a system that will consume a lot of space or that will require so much expertise to install. The easy it is to install, the less time it will absorb and most probably, the less installation cost you will incur.
If you have a larger generation need for off-grid applications, you’ll likely want to consider hiring a professional, mistakes can be very expensive.
When it comes to purchasing any item, the cost is a significant influencer. In selecting the best batteries for solar power storage, this is no different.
Although not always, price, in most cases, reflect the quality of an item.
Therefore, don’t rush into buying a battery just because it is cheap. You should consider all the other factors and compare them to the price.
As a general view on the solar panel battery cost, the higher the battery costs, the more benefits that come with it.
With charging time, some batteries charge faster than others. Different battery types will have varying charging rates with others being fast and others slow.
If you want to maximize the amount of energy generated from your solar panel system, then you need a fast charging solar battery. For those who care about the rate at which the battery charges, Gel batteries are the best choice for you.
Other categories of solar batteries such as the flooded lead-acid ones, take considerably more extended periods. They can take as long as even a whole day to get fully charged, which is long. Lithium-ion batteries, on the other hand, also have good charging speeds of around 3 hours.
If the battery charges fast, then the better for you as you can use the energy as fast as possible. A combination of an ideal battery and an excellent solar battery charger is vital to guarantee high charging speeds.
A manufacturer’s warranty is the next most crucial thing that you should take into consideration. Since the solar batteries are significantly expensive, you can’t afford to have a breakdown in the next few years after installation. It is wise to ensure any malfunction that may occur will be sorted.
The longer the warranty period, the best it is for you. Typically, more expensive brands offer more extended warranties than the less known and cheap ones. For solar storage batteries, a reasonable warranty period ranges somewhere from 20-30 years.
The lifespan of a battery means the period the battery will be useful before it loses its ability to hold a charge. You can measure solar batteries’ lifespan in terms of hours, days, or years, and the length depends on the type, size, or brand.
If you need a sure long-lasting and robust battery, be ready to dig a bit deeper into your wallet.
Long-lasting batteries will, in most cases, cost more than the lesser durable ones. Each brand of battery has its estimated amount of time they will remain useful. You should carefully check on this before you decide on the Solar cell to purchase.
All the batteries we offer on our web site, are quality batteries which we are happy to recommend. Should you have questions, please feel free to contact us here